Wednesday, March 6, 2013

How to Make a Styrene Roof for Carriages

One of the best ways to put a roof on any model carriage is to make a styrene roof curved to shape, to suit the carriage being built. This ensures that there is very little or no stresses from the roof material to “spring” the Urethane cast sides.

This is easily done by taking a sheet of .20”/ .5mm styrene sheet and cut to length and width to suit the carriage being roofed. It is good practice to add/allow an extra 5mm of material all round to ensure coverage is achieved – the excess material can be trimmed off in the final fitting.
Find a suitable length of steel tubing – if possible to the correct diameter required to suit the carriage kit end walls. I use a piece of steel tube I saved from a piece of exercise equipment (foot section), which had been discarded by a neighbor during a local shire, kerbside rubbish collection, but any metal tube can be used including vacuum cleaner pipe, pedestal fan etc.
Take the cut section of styrene sheet and tape the ends to the steel pipe using electrical tape ensuring that the styrene is square along the pipe. Then simply wind the tape tightly along the length of the pipe ensuring the styrene sheet is pulled tight onto the pipe
Take the pipe section and stand it in the kitchen sink ( I usually have the plastic side down) and prepare 2 full kettles of boiling water - I keep an old kettle spare for this purpose so that you have the water ready to go. With the water at boiling, carefully pour the boiled water down the inside of the tube – slowly I find is best, allowing more time for good heat transfer to the steel pipe.

Allow the pipe to cool and then remove the electrical tape to reveal a nicely shaped section of curved roof material.

Take the roof section and test fit it to carriage – carefully trim the long edge to achieve a neat fit to the carriage body – this might mean making several small cuts/trims till correct size is achieved - allow excess overhang on the ends to enable addition of bargeboards and carriage end trimmings.
Glue roof into place by firstly gluing (squarely) on the end walls then using a scalpel blade laden with glue on its top surface, gently lift the sides with the pointy end and push a little glue onto roof underside and then allow the roof to return to its position – hold in place until set and then tack a few more places. Once the roof is tacked into place, run a bead of glue down the inside of the body to seal along the length. Fit end detail and trim to length.

Friday, March 1, 2013

R Class Loco - 3D Printed

I had another delivery today from i.Materialise with the remaining major parts for the R class, these being the chassis and fuel tank.  I have now transferred the bogies, motor, DCC decoder and speaker from the temporary chassis to the 3D printed chassis, and the loco is running again!

The new parts are in grey in the photos below. (As always, click on the photo for a larger view.)

I haven't finished removing the small pieces of plastic from the support structure used in the 3D printing process, hence the numerous small bumps on the underneath of the chassis.  I have just cleaned up the parts enough to assemble and test the loco at this stage. I will have to dismantle it again for final cleanup, detailing and painting.

I designed the chassis with slots to accommodate two brass I-beams to give it some rigidity.  The real chassis is also based on two large I-beams.  The brass I-beams are a standard item from Special Shapes.

The fuel tank is hollow inside and can be filled with lead for weight.

 The headstocks have some detail included, including cowcatchers, and holes for brake and air hoses. The headstocks accommodate a Kadee long-shank whisker coupler.

Previous posts on the R Class: